BoilerFaultCodesYour boiler has detected an issue with the sensor that monitors external water flow temperature, meaning it cannot accurately gauge how much heat is needed for your system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: External flow sensor out of range or short circuit/External flow sensor measures a temperature outside of normal workingrange.
What causes this fault?
This fault occurs when the internal computer loses reliable communication with the sensor responsible for measuring the temperature of the water leaving the boiler. The most common reason is a physical failure of the sensor’s internal components or a loose connection in the wiring that prevents the system from reading accurate data. Because the boiler no longer knows how hot the water is, it shuts down as a safety precaution to prevent overheating.
This fault may become more apparent during the first cold snap of autumn when the heating system is pushed to operate at higher temperatures for the first time in months.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like FE95 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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